package com.klxedu.ms.gateway.security.access;

import java.util.Collection;
import java.util.Iterator;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.security.access.AccessDecisionManager;
import org.springframework.security.access.AccessDeniedException;
import org.springframework.security.access.ConfigAttribute;
import org.springframework.security.authentication.InsufficientAuthenticationException;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.GrantedAuthority;
import org.springframework.stereotype.Service;
import org.springframework.util.StringUtils;
/**
 * Title: CustomAccessDecisionManager<br>
 * Description: 访问决策器,用户是否拥有所请求资源的权限<br>
 * Copyright @ 2011~2018 Goldgov .All rights reserved.<br>
 * 
 * @author GuoR
 * @createDate 2018年7月17日
 */
@Service
public class CustomAccessDecisionManager implements AccessDecisionManager {
	private Log logger = LogFactory.getLog(this.getClass());

	@Override
	public void decide(Authentication authentication, Object object, Collection<ConfigAttribute> configAttributes)
			throws AccessDeniedException, InsufficientAuthenticationException {
		if (configAttributes == null) {
			return;
		}

		// 所请求的资源拥有的权限(一个资源对多个权限)
		Iterator<ConfigAttribute> iterator = configAttributes.iterator();
		while (iterator.hasNext()) {
			ConfigAttribute configAttribute = iterator.next();
			// 访问所请求资源所需要的权限
			String needPermission = configAttribute.getAttribute();
			if (StringUtils.isEmpty(needPermission)) {
				needPermission = configAttribute.toString();
			}
			logger.debug(getClass().getName() + " decide needPermission is " + needPermission);
			// 用户所拥有的权限authentication
			for (GrantedAuthority ga : authentication.getAuthorities()) {
				if (needPermission.trim().equals(ga.getAuthority().trim())) {
					return;
				}
			}
		}
		// 没有权限
		throw new AccessDeniedException(" 没有权限访问！ ");

	}

	@Override
	public boolean supports(ConfigAttribute attribute) {
		return true;
	}

	@Override
	public boolean supports(Class<?> clazz) {
		return true;
	}

}
